Selector: Drop support for EdgeHTML (i.e. non-Chromium Microsoft Edge)

Also, restrict some workarounds that were applied unconditionally in all
browsers to run only in IE now. This slightly increases the size but reduces
the performance burden on modern browsers that don't need the workarounds.

Also, clean up some comments.

Fixes jquerygh-4568

Author: mgol

src/ajax.js

@@ -542,7 +542,7 @@ jQuery.extend( {
 		if ( s.crossDomain == null ) {
 			urlAnchor = document.createElement( "a" );
 
-			// Support: IE <=8 - 11+, Edge 12 - 17 only
+			// Support: IE <=8 - 11+
 			// IE throws exception on accessing the href property if url is malformed,
 			// e.g. http://example.com:80x/
 			try {

src/core/DOMEval.js

@@ -17,13 +17,14 @@ function DOMEval( code, node, doc ) {
 	if ( node ) {
 		for ( i in preservedScriptAttributes ) {
 
-			// Support: Firefox <=64 - 66+, Edge <=18+
-			// Some browsers don't support the "nonce" property on scripts.
+			// Support: Firefox <=64 - 66+
+			// Firefox doesn't support the "nonce" property on scripts.
 			// On the other hand, just using `getAttribute` is not enough as
 			// the `nonce` attribute is reset to an empty string whenever it
 			// becomes browsing-context connected.
 			// See https://github.com/whatwg/html/issues/2369
 			// See https://html.spec.whatwg.org/#nonce-attributes
+			// See https://bugzilla.mozilla.org/show_bug.cgi?id=1389421
 			// The `node.getAttribute` check was added for the sake of
 			// `jQuery.globalEval` so that it can fake a nonce-containing node
 			// via an object.

src/core/isAttached.js

@@ -3,18 +3,18 @@ import documentElement from "../var/documentElement.js";
 
 import "../selector/contains.js"; // jQuery.contains
 
-var isAttached = function( elem ) {
-		return jQuery.contains( elem.ownerDocument, elem );
-	},
-	composed = { composed: true };
+var composed = { composed: true };
 
-// Support: IE 9 - 11+, Edge 12 - 18+
-// Check attachment across shadow DOM boundaries when possible (gh-3504)
-if ( documentElement.getRootNode ) {
-	isAttached = function( elem ) {
+// Support: IE 9 - 11+
+// Check attachment across shadow DOM boundaries when possible (gh-3504).
+// Provide a fallback for browsers without Shadow DOM v1 support.
+var isAttached = documentElement.getRootNode ?
+	function( elem ) {
 		return jQuery.contains( elem.ownerDocument, elem ) ||
 			elem.getRootNode( composed ) === elem.ownerDocument;
+	} :
+	function( elem ) {
+		return jQuery.contains( elem.ownerDocument, elem );
 	};
-}
 
 export default isAttached;

src/css.js

@@ -11,7 +11,6 @@ import getStyles from "./css/var/getStyles.js";
 import swap from "./css/var/swap.js";
 import curCSS from "./css/curCSS.js";
 import adjustCSS from "./css/adjustCSS.js";
-import support from "./css/support.js";
 import finalPropName from "./css/finalPropName.js";
 
 import "./core/init.js";
@@ -135,15 +134,18 @@ function getWidthOrHeight( elem, dimension, extra ) {
 	}
 
 
-	// Support: IE 9 - 11+
-	// Use offsetWidth/offsetHeight for when box sizing is unreliable.
-	// In those cases, the computed value can be trusted to be border-box.
-	if ( ( isIE && isBorderBox ||
+	if ( ( isIE && (
 
-		// Support: IE 10 - 11+, Edge 15 - 18+
-		// IE/Edge misreport `getComputedStyle` of table rows with width/height
-		// set in CSS while `offset*` properties report correct values.
-		!support.reliableTrDimensions() && nodeName( elem, "tr" ) ||
+			// Support: IE 9 - 11+
+			// Use offsetWidth/offsetHeight for when box sizing is unreliable.
+			// In those cases, the computed value can be trusted to be border-box.
+			isBorderBox ||
+
+			// Support: IE 10 - 11+
+			// IE misreports `getComputedStyle` of table rows with width/height
+			// set in CSS while `offset*` properties report correct values.
+			nodeName( elem, "tr" )
+		) ||
 
 		// Fall back to offsetWidth/offsetHeight when value is "auto"
 		// This happens for inline elements with no explicit setting (gh-3571)

src/css/cssCamelCase.js

@@ -5,7 +5,7 @@ var rmsPrefix = /^-ms-/;
 
 // Convert dashed to camelCase, handle vendor prefixes.
 // Used by the css & effects modules.
-// Support: IE <=9 - 11+, Edge 12 - 18+
+// Support: IE <=9 - 11+
 // Microsoft forgot to hump their vendor prefix (#9572)
 function cssCamelCase( string ) {
 	return camelCase( string.replace( rmsPrefix, "ms-" ) );

src/css/support.js

@@ -143,10 +143,9 @@ function defaultPrefilter( elem, props, opts ) {
 	// Restrict "overflow" and "display" styles during box animations
 	if ( isBox && elem.nodeType === 1 ) {
 
-		// Support: IE <=9 - 11+, Edge 12 - 18+
+		// Support: IE <=9 - 11+
 		// Record all 3 overflow attributes because IE does not infer the shorthand
-		// from identically-valued overflowX and overflowY and Edge just mirrors
-		// the overflowX value there.
+		// from identically-valued overflowX and overflowY.
 		opts.overflow = [ style.overflow, style.overflowX, style.overflowY ];
 
 		// Identify a display type, preferring old show/hide data over the CSS cascade

src/effects.js

@@ -26,8 +26,8 @@ var
 	// See https://github.com/eslint/eslint/issues/3229
 	rxhtmlTag = /<(?!area|br|col|embed|hr|img|input|link|meta|param)(([a-z][^\/\0>\x20\t\r\n\f]*)[^>]*)\/>/gi,
 
-	// Support: IE <=10 - 11+, Edge 12 - 13 only
-	// In IE/Edge using regex groups here causes severe slowdowns.
+	// Support: IE <=10 - 11+
+	// In IE using regex groups here causes severe slowdowns.
 	// See https://connect.microsoft.com/IE/feedback/details/1736512/
 	rnoInnerhtml = /<script|<style|<link/i,
 

src/manipulation.js

@@ -7,7 +7,7 @@ import pop from "./var/pop.js";
 import push from "./var/push.js";
 import whitespace from "./selector/var/whitespace.js";
 import rbuggyQSA from "./selector/rbuggyQSA.js";
-import support from "./selector/support.js";
+import isIE from "./var/isIE.js";
 
 // The following utils are attached directly to the jQuery object.
 import "./selector/contains.js";
@@ -131,9 +131,9 @@ var i,
 	},
 
 	// Used for iframes; see `setDocument`.
-	// Support: IE 9 - 11+, Edge 12 - 18+
+	// Support: IE 9 - 11+
 	// Removing the function wrapper causes a "Permission Denied"
-	// error in IE/Edge.
+	// error in IE.
 	unloadHandler = function() {
 		setDocument();
 	},
@@ -150,7 +150,7 @@ function selectorError( msg ) {
 }
 
 function find( selector, context, results, seed ) {
-	var m, i, elem, nid, match, groups, newSelector,
+	var m, i, elem, nid, match, groups, newSelector, canUseScope,
 		newContext = context && context.ownerDocument,
 
 		// nodeType defaults to 9, since context defaults to document
@@ -231,9 +231,10 @@ function find( selector, context, results, seed ) {
 
 					// We can use :scope instead of the ID hack if the browser
 					// supports it & if we're not changing the context.
-					if ( newContext !== context || !support.scope ) {
+					canUseScope = newContext === context && !isIE;
 
-						// Capture the context ID, setting it first if necessary
+					// Capture the context ID, setting it first if necessary
+					if ( !canUseScope ) {
 						if ( ( nid = context.getAttribute( "id" ) ) ) {
 							nid = jQuery.escapeSelector( nid );
 						} else {
@@ -360,7 +361,6 @@ function createDisabledPseudo( disabled ) {
 				return elem.isDisabled === disabled ||
 
 					// Where there is no isDisabled, check manually
-					/* jshint -W018 */
 					elem.isDisabled !== !disabled &&
 						inDisabledFieldset( elem ) === disabled;
 			}
@@ -419,8 +419,8 @@ function setDocument( node ) {
 		doc = node ? node.ownerDocument || node : preferredDoc;
 
 	// Return early if doc is invalid or already selected
-	// Support: IE 11+, Edge 17 - 18+
-	// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+	// Support: IE 11+
+	// IE sometimes throws a "Permission denied" error when strict-comparing
 	// two documents; shallow comparisons work.
 	// eslint-disable-next-line eqeqeq
 	if ( doc == document || doc.nodeType !== 9 ) {
@@ -432,16 +432,14 @@ function setDocument( node ) {
 	documentElement = document.documentElement;
 	documentIsHTML = !jQuery.isXMLDoc( document );
 
-	// Support: IE 9 - 11+, Edge 12 - 18+
+	// Support: IE 9 - 11+
 	// Accessing iframe documents after unload throws "permission denied" errors (jQuery #13936)
-	// Support: IE 11+, Edge 17 - 18+
-	// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+	// Support: IE 11+
+	// IE sometimes throws a "Permission denied" error when strict-comparing
 	// two documents; shallow comparisons work.
 	// eslint-disable-next-line eqeqeq
-	if ( preferredDoc != document &&
+	if ( isIE && preferredDoc != document &&
 		( subWindow = document.defaultView ) && subWindow.top !== subWindow ) {
-
-		// Support: IE 9 - 11+, Edge 12 - 18+
 		subWindow.addEventListener( "unload", unloadHandler );
 	}
 }
@@ -1410,8 +1408,8 @@ function matcherFromGroupMatchers( elementMatchers, setMatchers ) {
 
 			if ( outermost ) {
 
-				// Support: IE 11+, Edge 17 - 18+
-				// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+				// Support: IE 11+
+				// IE sometimes throws a "Permission denied" error when strict-comparing
 				// two documents; shallow comparisons work.
 				// eslint-disable-next-line eqeqeq
 				outermostContext = context == document || context || outermost;
@@ -1422,8 +1420,8 @@ function matcherFromGroupMatchers( elementMatchers, setMatchers ) {
 				if ( byElement && elem ) {
 					j = 0;
 
-					// Support: IE 11+, Edge 17 - 18+
-					// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+					// Support: IE 11+
+					// IE sometimes throws a "Permission denied" error when strict-comparing
 					// two documents; shallow comparisons work.
 					// eslint-disable-next-line eqeqeq
 					if ( !context && elem.ownerDocument != document ) {

src/selector.js

@@ -1,29 +1,19 @@
-import document from "../var/document.js";
 import isIE from "../var/isIE.js";
 import whitespace from "./var/whitespace.js";
 
-var rbuggyQSA = [],
-	testEl = document.createElement( "div" ),
-	input = document.createElement( "input" );
+var rbuggyQSA = isIE && new RegExp(
 
-// Support: IE 9 - 11+
-// IE's :disabled selector does not pick up the children of disabled fieldsets
-if ( isIE ) {
-	rbuggyQSA.push( ":enabled", ":disabled" );
-}
+	// Support: IE 9 - 11+
+	// IE's :disabled selector does not pick up the children of disabled fieldsets
+	":enabled|:disabled|" +
 
-// Support: IE 11+, Edge 15 - 18+
-// IE 11/Edge don't find elements on a `[name='']` query in some cases.
-// Adding a temporary attribute to the document before the selection works
-// around the issue.
-// Interestingly, IE 10 & older don't seem to have the issue.
-input.setAttribute( "name", "" );
-testEl.appendChild( input );
-if ( !testEl.querySelectorAll( "[name='']" ).length ) {
-	rbuggyQSA.push( "\\[" + whitespace + "*name" + whitespace + "*=" +
-		whitespace + "*(?:''|\"\")" );
-}
+	// Support: IE 11+
+	// IE 11 doesn't find elements on a `[name='']` query in some cases.
+	// Adding a temporary attribute to the document before the selection works
+	// around the issue.
+	"\\[" + whitespace + "*name" + whitespace + "*=" +
+		whitespace + "*(?:''|\"\")"
 
-rbuggyQSA = rbuggyQSA.length && new RegExp( rbuggyQSA.join( "|" ) );
+);
 
 export default rbuggyQSA;

src/selector/rbuggyQSA.js

@@ -20,8 +20,8 @@ function sortOrder( a, b ) {
 	}
 
 	// Calculate position if both inputs belong to the same document
-	// Support: IE 11+, Edge 17 - 18+
-	// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+	// Support: IE 11+
+	// IE sometimes throws a "Permission denied" error when strict-comparing
 	// two documents; shallow comparisons work.
 	// eslint-disable-next-line eqeqeq
 	compare = ( a.ownerDocument || a ) == ( b.ownerDocument || b ) ?
@@ -34,17 +34,17 @@ function sortOrder( a, b ) {
 	if ( compare & 1 ) {
 
 		// Choose the first element that is related to the document
-		// Support: IE 11+, Edge 17 - 18+
-		// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+		// Support: IE 11+
+		// IE sometimes throws a "Permission denied" error when strict-comparing
 		// two documents; shallow comparisons work.
 		// eslint-disable-next-line eqeqeq
 		if ( a == document || a.ownerDocument == document &&
 			jQuery.contains( document, a ) ) {
 			return -1;
 		}
 
-		// Support: IE 11+, Edge 17 - 18+
-		// IE/Edge sometimes throw a "Permission denied" error when strict-comparing
+		// Support: IE 11+
+		// IE sometimes throws a "Permission denied" error when strict-comparing
 		// two documents; shallow comparisons work.
 		// eslint-disable-next-line eqeqeq
 		if ( b == document || b.ownerDocument == document &&

src/selector/support.js

@@ -1,7 +1,7 @@
 import arr from "./arr.js";
 
-// Support: IE 11+, Edge 18+
-// Provide fallback for browsers without Array#flat.
+// Support: IE 11+
+// IE doesn't have Array#flat; provide a fallback.
 export default arr.flat ? function( array ) {
 	return arr.flat.call( array );
 } : function( array ) {

src/selector/uniqueSort.js

@@ -47,8 +47,8 @@
 	// This doesn't apply to iframes because they synchronously expect jQuery to be there.
 	if ( config.esmodules && QUnit ) {
 
-		// Support: IE 11+, Edge 12 - 18+
-		// IE/Edge don't support the dynamic import syntax so they'd crash
+		// Support: IE 11+
+		// IE doesn't support the dynamic import syntax so it would crash
 		// with a SyntaxError here.
 		dynamicImportSource = "" +
 			"import( `${ parentUrl }src/jquery.js` )\n" +

src/var/flat.js

@@ -267,7 +267,7 @@ QUnit.module( "ajax", {
 				"Nullable": null,
 				"undefined": undefined
 
-				// Support: IE 9 - 11+, Edge 12 - 14 only
+				// Support: IE 9 - 11+
 				// IE can receive empty headers but not send them.
 			}, QUnit.isIE ? {} : {
 				"Empty": ""

test/jquery.js

@@ -788,9 +788,9 @@ QUnit.test( "jQuery.map", function( assert ) {
 	assert.equal( result.length, 3, "Array flatten only one level down" );
 	assert.ok( Array.isArray( result[ 0 ] ), "Array flatten only one level down" );
 
-	// Support: IE 11+, Edge 18+
-	// Skip the test in browsers without Array#flat.
-	if ( Array.prototype.flat ) {
+	// Support: IE 11+
+	// IE doesn't have Array#flat so it'd fail the test.
+	if ( QUnit.isIE ) {
 		result = jQuery.map( Array( 300000 ), function( v, k ) {
 			return k;
 		} );